3D World Actions

Built-in authoring reference for Mercury 1.0.1. All actions.

Add Streaming Source

Registers one Object type as an additional streaming source. Every live copy keeps nearby scenery loaded; removal and clearing are separate actions.

Reference key: streamingSource.

Editor category: 3D World > 3D World Streaming.

Availability: 3D Logic only.

Example: On Create [Caravan], add this Object as a streaming source so the road ahead stays loaded.

Parameter	Type	Optional	Details
Source	enum	Yes	Register this Object type, or choose another Object by name. Choices: thisObject, byName. Default: “thisObject”.
Object	thing:object	Yes	The Object whose live copies become streaming sources. Shown when Source is byName.

Aim Bone At

Rotates one bone toward a target, layered over the playing animation until released. Two-bone reaching is a separate Atomic action.

Reference key: boneLookAt.

Editor category: 3D World > 3D Inverse Kinematics.

Availability: 3D Logic only.

Example: Aim Head at Player so the character tracks the player while its walk animation continues.

Choose the target instance with the Action’s Applies To field.

Parameter	Type	Optional	Details
Bone	text	No	The one bone to rotate toward the target. Partial names match.
Target	thing:object	Yes	The object to track (its first live instance). Blank releases this aim controller back to the animation.
Tracking Speed	number	Yes	The fraction of the remaining turn taken each frame — 1 snaps, 0.1 turns smoothly. Default: 0.15.

Animate IK Weight

Changes a named IK constraint’s weight over the selected duration. Weight 0 leaves the animation pose; weight 1 applies the full constraint.

Reference key: animateIKWeight.

Editor category: 3D World > 3D Inverse Kinematics.

Availability: 3D Logic only.

Example: On Custom Event [notice]: Animate IK Weight [look] to [1] over [0.4] seconds.

Choose the target instance with the Action’s Applies To field.

Parameter	Type	Optional	Details
IK Constraint	text	No	An IK constraint by name, authored in the 3D Model’s IK section.
Weight	number	No	0 = pure animation, 1 = full IK. Default: 1.
Seconds	number	Yes	0 applies instantly. Default: 0.3.

Animate Material

Changes one property of the live instance’s Model materials over the selected duration. It applies to an assigned Material override or the Model’s stored materials.

Reference key: animateMaterial.

Editor category: 3D World > 3D Materials.

Availability: 3D Logic only.

Example: When the forge lights: Animate Material [emissiveIntensity] to [6] over [0.8] seconds.

Choose the target instance with the Action’s Applies To field.

Parameter	Type	Optional	Details
Property	enum	No	Which material property to animate. Choices: metallic, roughness, alpha, emissiveIntensity, baseColor, emissiveColor. Default: “roughness”.
To Value	number	No	The target — 0..1 for the sliders, up to 10 for emissive intensity, or a #rrggbb color for the color properties. Default: 1.
Seconds	number	Yes	0 applies instantly. Default: 0.5.

Change 3D Light Property

Changes exactly one property of one placed 3D light and preserves every unrelated live override.

Reference key: set3dLightProperty.

Editor category: 3D World > 3D Lights and Shadows.

Availability: 3D Logic only.

Parameter	Type	Optional	Details
Placed Light	text	No	The stable Name of a point or spot light placed in the 3D Scene.
Property	enum	No	Choose one of the listed options. Choices: enabled, color, intensity, range. Default: “intensity”.
Value	mixed	No	The one new property value. Enabled accepts true/false/toggle, Color accepts a hex color or text variable, and Intensity/Range accept numeric expressions. Shown when Property has a selection.

Change 3D Shadow Property

Changes exactly one dynamic-shadow property while preserving every unrelated shadow setting.

Reference key: set3dShadowProperty.

Editor category: 3D World > 3D Lights and Shadows.

Availability: 3D Logic only.

Parameter	Type	Optional	Details
Light	text	Yes	Blank targets the sun. A placed light Name targets that light for Casting or Strength; Quality is scene-wide.
Property	enum	No	Choose one of the listed options. Choices: casting, quality, strength. Default: “strength”.
Value	mixed	No	The one new property value. Casting accepts true/false, Quality accepts off/low/medium/high/ultra or a text variable, and Strength accepts a numeric expression from 0 to 1. Shown when Property has a selection.

Change Baked Lighting Property

Changes exactly one baked-lighting property while preserving the other baked-light state.

Reference key: setBakedLightingProperty.

Editor category: 3D World > 3D Atmosphere and Global Lighting.

Availability: 3D Logic only.

Parameter	Type	Optional	Details
Property	enum	No	Choose one of the listed options. Choices: enabled, brightness. Default: “brightness”.
Value	mixed	No	The one new property value. Enabled accepts true/false; Brightness accepts a numeric expression. Shown when Property has a selection.
Seconds	number	Yes	0 applies immediately. A positive duration fades Brightness to its new value. Default: 0. Shown when Property is brightness.

Change Camera Rig Property

Changes exactly one 3D camera-rig property, optionally over time, while preserving every unrelated camera setting.

Reference key: setCameraRigProperty.

Editor category: 3D World > 3D Cameras.

Availability: 3D Logic only.

Example: Change Camera Rig Property [dolly] to [22] over [1.2] seconds.

Parameter	Type	Optional	Details
Property	enum	No	Choose one of the listed options. Choices: pitch, field of view, dolly, yaw. Default: “pitch”.
Value	mixed	No	The one new rig value: Pitch and Yaw are degrees, Field of View is degrees, and Dolly is measured in blocks. Shown when Property has a selection.
Seconds	number	Yes	0 applies immediately. A positive duration eases only this property to its new value. Default: 0.

Change Character Controller Property

Changes exactly one capsule-controller property while preserving every unrelated controller setting.

Reference key: setCharacterControllerProperty.

Editor category: 3D World > 3D Characters and Vehicles.

Availability: 3D Logic only.

Example: Change Character Controller Property [radius] to [0.2].

Parameter	Type	Optional	Details
Property	enum	No	Choose one of the listed options. Choices: enabled, radius, height. Default: “enabled”.
Value	mixed	No	The one new controller value. Enabled accepts true/false; Radius and Height accept numeric block measurements. Shown when Property has a selection.

Change Foliage Property

Changes exactly one foliage property while preserving every unrelated type and quality setting.

Reference key: setFoliageProperty.

Editor category: 3D World > 3D Blocks and Terrain.

Availability: 3D Logic only.

Parameter	Type	Optional	Details
Type	text	Yes	A foliage type Name. Blank targets every type for Visible or Density; Detail is scene-wide.
Property	enum	No	Choose one of the listed options. Choices: visible, density, detail. Default: “visible”.
Value	mixed	No	The one new property value. Visible accepts true/false, Density accepts a numeric expression from 0 to 1, and Detail accepts off/low/medium/high/ultra or a text variable. Shown when Property has a selection.

Change Global Illumination Property

Changes exactly one realtime global-illumination property while preserving the other bounce settings.

Reference key: setGlobalIlluminationProperty.

Editor category: 3D World > 3D Atmosphere and Global Lighting.

Availability: 3D Logic only.

Parameter	Type	Optional	Details
Property	enum	No	Choose one of the listed options. Choices: enabled, strength, spread. Default: “strength”.
Value	mixed	No	The one new property value. Enabled accepts true/false; Strength and Spread accept numeric expressions. Shown when Property has a selection.
Seconds	number	Yes	0 applies immediately. A positive duration eases this one property to its new value. Default: 0. Shown when Property is one of strength, spread.

Change Reflection Property

Changes exactly one screen-space-reflection property while preserving every unrelated reflection setting.

Reference key: setReflectionProperty.

Editor category: 3D World > 3D Atmosphere and Global Lighting.

Availability: 3D Logic only.

Parameter	Type	Optional	Details
Property	enum	No	Choose one of the listed options. Choices: enabled, strength, max distance, surface thickness, softness. Default: “strength”.
Value	mixed	No	The one new property value. Enabled accepts true/false; every other property accepts a numeric expression. Shown when Property has a selection.
Seconds	number	Yes	0 applies immediately. A positive duration eases this one reflection property to its new value. Default: 0. Shown when Property is one of strength, max distance, surface thickness, softness.

Change Vehicle System Property

Changes exactly one scene-wide vehicle-system property while preserving every unrelated vehicle setting.

Reference key: setVehicleSystemProperty.

Editor category: 3D World > 3D Characters and Vehicles.

Availability: 3D Logic only.

Example: Change Vehicle System Property [grip] to [0.15].

Parameter	Type	Optional	Details
Property	enum	No	Choose one of the listed options. Choices: enabled, top speed, grip. Default: “enabled”.
Value	mixed	No	The one new vehicle-system value. Enabled accepts true/false; Top Speed and Grip accept numeric expressions. Shown when Property has a selection.

Change Volumetric Clouds Property

Changes exactly one volumetric-cloud property. Optional duration belongs to that one transition; every unrelated cloud setting is preserved.

Reference key: setVolumetricCloudsProperty.

Editor category: 3D World > 3D Atmosphere and Global Lighting.

Availability: 3D Logic only.

Parameter	Type	Optional	Details
Property	enum	No	Choose one of the listed options. Choices: enabled, tint, coverage, density, altitude, thickness, wind direction, wind speed, sky light. Default: “coverage”.
Value	mixed	No	The one new property value. Enabled accepts true/false; Tint accepts a hex color or text variable; every other property accepts a numeric expression. Shown when Property has a selection.
Seconds	number	Yes	0 applies immediately. A positive duration eases this one property to its new value. Default: 0. Shown when Property is one of tint, coverage, density, altitude, thickness, wind direction, wind speed, sky light.

Change Volumetric Fog Property

Changes exactly one volumetric-fog property. Optional duration belongs to that one transition; every unrelated fog setting is preserved.

Reference key: setVolumetricFogProperty.

Editor category: 3D World > 3D Atmosphere and Global Lighting.

Availability: 3D Logic only.

Parameter	Type	Optional	Details
Property	enum	No	Choose one of the listed options. Choices: enabled, color, density, height, falloff, start distance, wisps, wind direction, wind speed, sun glow. Default: “density”.
Value	mixed	No	The one new property value. Enabled accepts true/false; Color accepts a hex color or text variable; every other property accepts a numeric expression. Shown when Property has a selection.
Seconds	number	Yes	0 applies immediately. A positive duration eases this one property to its new value. Default: 0. Shown when Property is one of color, density, height, falloff, start distance, wisps, wind direction, wind speed, sun glow.

Change Water Property

Changes exactly one 3D-water property of one water body while preserving the level, waves, color, and opacity not named by this action.

Reference key: setWaterProperty.

Editor category: 3D World > 3D Blocks and Terrain.

Availability: 3D Logic only.

Parameter	Type	Optional	Details
Property	enum	No	Choose one of the listed options. Choices: enabled, level, wave height, wave speed, color, opacity. Default: “level”.
Value	mixed	No	The one new property value. Enabled accepts true/false; Color accepts a hex color or text variable; every other property accepts a numeric expression. Shown when Property has a selection.
Water Body	text	Yes	Which water body to retune — its name from the Water section, or its number (1 = the scene’s own table). Blank means body 1, which is what a scene with one water table has always had.

Change World Streaming Property

Changes exactly one world-streaming property while preserving every unrelated streaming setting.

Reference key: setWorldStreamingProperty.

Editor category: 3D World > 3D World Streaming.

Availability: 3D Logic only.

Example: Change World Streaming Property [radius] to [220].

Parameter	Type	Optional	Details
Property	enum	No	Choose one of the listed options. Choices: enabled, radius. Default: “enabled”.
Value	mixed	No	The one new streaming value. Enabled accepts true/false; Radius accepts a numeric block distance. Shown when Property has a selection.

Clear Block

Removes the block at the selected 3D Scene cell.

Reference key: clearBlock.

Editor category: 3D World > 3D Blocks and Terrain.

Availability: 3D Logic only.

Example: The bomb’s explosion clears the cracked wall block at its cell.

Parameter	Type	Optional	Details
Cell X	number	No	Expression or literal value.
Cell Y	number	No	Expression or literal value.
Cell Z (Level)	number	No	Expression or literal value.

Clear Streaming Sources

Removes every additional Object streaming source. The camera remains a streaming source, and world-streaming configuration is unchanged.

Reference key: clearStreamingSources.

Editor category: 3D World > 3D World Streaming.

Availability: 3D Logic only.

Example: When leaving an open-world mode, clear all additional streaming sources.

Feed Viewed Creature

Feeds the creature under the crosshair its configured Tame Item from the player’s inventory. A wild creature becomes tame. Two nearby tame adults of the same kind can breed when fed; other eligible feedings heal the creature. The operation publishes the taming or breeding Event.

Reference key: feedCreature.

Editor category: 3D World > 3D Voxel Survival.

Availability: 3D Logic only.

Example: Holding Leaves, pressing Use on a Meadow Hopper tames it; feeding two tame hoppers standing together breeds a baby.

Parameter	Type	Optional	Details
Item	text	Yes	Blank feeds the selected hotbar item.
Reach (meters)	number	Yes	Blank uses the standard 3.5-meter reach (0.5–8).

Fill Blocks

Fills the box of cells between two corners with the selected block. A blank Block clears that box. Changed chunks remesh after the operation. A box larger than 262,144 cells is refused with a Console message.

Reference key: fillBlocks.

Editor category: 3D World > 3D Blocks and Terrain.

Availability: 3D Logic only.

Example: On scene start: Fill Blocks (0,0,0) to (31,31,0) with Terrain “Grass” lays the island’s whole ground in one action.

Parameter	Type	Optional	Details
From Cell X	number	No	Expression or literal value.
From Cell Y	number	No	Expression or literal value.
From Cell Z (Level)	number	No	Expression or literal value.
To Cell X	number	No	Expression or literal value.
To Cell Y	number	No	Expression or literal value.
To Cell Z (Level)	number	No	Expression or literal value.
Tileset	thing:tileset	Yes	The tileset whose block palette to place from. Blank (with a blank Block) clears the box instead.
Block	text	Yes	The palette block name to fill with. Blank clears the box.

Fire Animator Trigger

Fires a named Trigger parameter on the live instance’s 3D Animator. The trigger remains latched until a transition consumes it.

Reference key: fireAnimTrigger.

Editor category: 3D World > 3D Animation.

Availability: 3D Logic only.

Example: On Button Pressed [Attack]: Fire Animator Trigger [attack].

Choose the target instance with the Action’s Applies To field.

Parameter	Type	Optional	Details
Trigger	text	No	Text value; some actions also accept $global names.

Forward+ Lights

Turns Forward+ clustered lighting on or off for lights included in the exported Scene. The authored Lighting setting determines the built light budget; turning this on cannot add lights omitted at export. Shadow-casting and lightmap-baked lights use the classic lighting path.

Reference key: setForwardPlusLights.

Editor category: 3D World > 3D Atmosphere and Global Lighting.

Availability: 3D Logic only.

Example: On Custom Event [nightMarket]: Forward+ Lights on — every stall lantern lights the crowd at once.

Parameter	Type	Optional	Details
Clustered Lights	enum	No	On pools placed point/spot lights into one screen-tiled cluster; Off returns them to classic forward lighting. Choices: on, off. Default: “on”.

Generate Random 3D Vector

Makes one random Vec3 distributed evenly around a sphere. Later expressions can read the complete value or its X, Y, and Z members; use Change Variable only to retain a copy.

Reference key: generateRandomVector3D.

Editor category: 3D World > 3D Random and Noise.

Availability: 3D Logic only.

Example: Generate a 3D vector from length [4] to [8], then store randomVector3DResult.value or read randomVector3DResult.value.z.

Parameter	Type	Optional	Details
Minimum Length	number	No	The shortest possible vector length. Negative values are treated as zero. Default: 0.
Maximum Length	number	No	The longest possible vector length. Reversed endpoints are accepted. Default: 1.

Results

Field	Type	Description
value	vec3
value.x	number
value.y	number
value.z	number

Paint Terrain

Applies the terrain paint brush at a world point. Configure Terrain Paint layers in the Scene’s Terrain Mode before using this Action.

Reference key: paintTerrain.

Editor category: 3D World > 3D Blocks and Terrain.

Availability: 3D Logic only.

Example: Every Frame while the lava elemental walks: Paint Terrain at [self.x] [self.y] radius [24] layer [3] — a scorched trail follows it.

Parameter	Type	Optional	Details
Position Relative To	enum	Yes	World uses absolute scene coordinates. Object uses local offsets from the acting Object. Coordinate uses local offsets from a named Coordinate. Bounding Box uses local offsets from a selected Transform bounding-box anchor. Choices: world, object, coordinate, boundingBox. Default: “world”.
Coordinate	text	Yes	A named Coordinate on the acting Object. Used only when Position Relative To is Coordinate.
Bounding Box Anchor	enum	Yes	A point on the acting Object’s Transform bounding box. Used only when Position Relative To is Bounding Box. Choices: center, top, bottom, left, right, topLeft, topRight, bottomLeft, bottomRight. Default: “center”.
X	number	No	World X (m) of the brush center — an instance’s x paints under its feet.
Y	number	No	World Y (m) of the brush center.
Radius (m)	number	Yes	Brush radius in meters. Default: 2.
Layer	number	Yes	Which paint layer to apply, 1–4 (the Terrain Paint list order; 1 is the base coat). Default: 2.
Strength %	number	Yes	0–100 flow per stamp (blank = 75). Low values build up over repeated stamps.
Erase	boolean	Yes	Remove the layer’s paint instead, revealing the coats beneath it. Default: false.

Photo Mode

Opens a paused 3D photo view with orbit, exposure, and focus controls inside the authored camera limits. Closing it restores the previous framing, rendering settings, and pause state.

Reference key: photoMode3d.

Editor category: 3D World > 3D Cameras.

Availability: 3D Logic only.

Example: When [F2] is pressed: Photo Mode [toggle].

Parameter	Type	Optional	Details
Mode	enum	No	Open pauses the world and hands the player the photo booth; Close restores everything it touched. Choices: open, close, toggle. Default: “open”.

Place Held Block

Places the block of the selected inventory slot in the empty cell in front of the block face under the crosshair, using one from the stack (creative mode keeps it). The block turns to face the player when it can. In multiplayer the host confirms the placement. Results publish as $place_ok and $place_reason (empty, block, occupied, no-target, inventory, rejected) with $place_x, $place_y, $place_z, $place_block and $place_item; Block Placed fires on success. 3D block-world scenes (first-person camera) on the Babylon engine only.

Reference key: placeViewedBlock.

Editor category: 3D World > 3D Voxel Survival.

Availability: 3D Logic only.

Example: On Button Pressed [Place]: Place Held Block from [Voxel Inventory].

Parameter	Type	Optional	Details
Inventory Table	thing:data	Yes	The slotted inventory to place from. Blank uses the Survival Kit inventory.

Play Animator State

Selects a named state on the live instance’s 3D Animator and blends over Blend Seconds. This bypasses transition conditions. Choose Layer to address a named layer instead of the base graph.

Reference key: playAnimState.

Editor category: 3D World > 3D Animation.

Availability: 3D Logic only.

Example: The defeat cutscene runs Play Animator State [Collapse] with a slow 0.6s blend.

Choose the target instance with the Action’s Applies To field.

Parameter	Type	Optional	Details
State	text	No	Text value; some actions also accept $global names.
Blend Seconds	number	Yes	Number value; decimals are allowed. Default: 0.2.
Layer	text	Yes	An Animator layer name. Blank drives the base machine.

Reach Bone Toward

Applies two-bone reaching after the animation pose each frame until released. Select the chain and target so the end bone can reach the requested point.

Reference key: boneReach.

Editor category: 3D World > 3D Inverse Kinematics.

Availability: 3D Logic only.

Example: Near a lever: Reach Bone Toward — bone [forearm.R], target [Lever].

Choose the target instance with the Action’s Applies To field.

Parameter	Type	Optional	Details
Bone	text	No	The LOWER bone of the two-bone chain — the forearm for a hand reach, the shin for a foot plant.
Target	thing:object	Yes	The object to reach for (its first live instance). Blank releases the chain back to the animation.
Bend Angle	number	Yes	Rolls the bend direction around the chain (degrees) — point the elbow out, the knee forward. Default: 0.

Refresh Reflection Probes

Updates every Scene Reflection Probe cubemap using the current world. Use it after changes that should appear in reflections. Probes also have their authored startup and timed refresh behavior.

Reference key: refreshReflectionProbes.

Editor category: 3D World > 3D Atmosphere and Global Lighting.

Availability: 3D Logic only.

Example: On Custom Event [nightfall]: Set Time of Day [22], then Refresh Reflection Probes — the throne room’s gold now mirrors the torchlight sky.

Remove Streaming Source

Removes one Object type from the streaming-source roster without changing other registered sources or streaming configuration.

Reference key: removeStreamingSource.

Editor category: 3D World > 3D World Streaming.

Availability: 3D Logic only.

Example: When a caravan is retired, remove its Object type as a streaming source.

Parameter	Type	Optional	Details
Source	enum	Yes	Unregister this Object type, or choose another Object by name. Choices: thisObject, byName. Default: “thisObject”.
Object	thing:object	Yes	The Object to remove from the streaming-source roster. Shown when Source is byName.

Sample 3D Noise

Samples smooth deterministic spatial noise from -1 to 1. Later expressions can read the produced value directly; identical inputs always return the same value.

Reference key: sampleNoise3D.

Editor category: 3D World > 3D Random and Noise.

Availability: 3D Logic only.

Example: Sample 3D noise through X, Y, and Height with Frequency [0.02] to shape a volumetric effect.

Parameter	Type	Optional	Details
X	number	No	The horizontal position in the noise field. Default: 0.
Y	number	No	The depth position in the noise field. Default: 0.
Height	number	No	The vertical position in the noise field. Default: 0.
Frequency	number	No	Scales all coordinates before sampling. Smaller values change more gradually. Default: 0.01.
Seed	number	No	A whole-number seed selecting a repeatable noise field. Default: 0.

Results

Field	Type	Description
value	number

Sculpt Ground

Digs or raises Smooth ground a little at a time instead of whole blocks: a Smooth block’s surface lowers inside its cell as its fill drops, the block is removed when nothing is left, and raising the empty cell above full Smooth ground grows a new one. Other blocks are left alone.

Reference key: sculptGround.

Editor category: 3D World > 3D Blocks and Terrain.

Availability: 3D Logic only.

Example: While the shovel key is held: Sculpt Ground at the target cell, Amount -0.125, Radius 2.

Parameter	Type	Optional	Details
Cell X	number	No	Expression or literal value.
Cell Y	number	No	Expression or literal value.
Cell Z (Level)	number	No	Expression or literal value.
Amount	number	No	How much ground to add (positive) or dig away (negative), in blocks of fill: -0.25 digs a quarter of a block. Fill is kept in sixteenths. Default: -0.25.
Radius	number	Yes	0 sculpts the one cell. Above 0 sculpts every Smooth block within that many blocks (up to 8), strongest at the centre. Default: 0.

Select Hotbar Slot

Makes one hotbar slot the selected slot: the item the player holds and the block Place Held Block places. Publishes $voxel_selected_slot. A position with no hotbar slot changes nothing. 3D block-world scenes on the Babylon engine only.

Reference key: selectHotbarSlot.

Editor category: 3D World > 3D Voxel Survival.

Availability: 3D Logic only.

Example: On Button Pressed [Hotbar 2]: Select Hotbar Slot [2].

Parameter	Type	Optional	Details
Hotbar Position	number	No	1 is the first hotbar slot (up to 9). Used by Set. Default: 1.
Inventory Table	thing:data	Yes	The slotted inventory. Blank uses the Survival Kit inventory.
Mode	enum	Yes	Set picks Hotbar Position; Next and Previous step from the selected slot and wrap around the hotbar (bind them to the mouse wheel). Choices: set, next, previous. Default: “set”.

Set Animator Controller

Assigns a different 3D Animator controller to the live instance. Use the separate Actions for state playback, parameter values, triggers, and speed.

Reference key: setAnimator.

Editor category: 3D World > 3D Animation.

Availability: 3D Logic only.

Example: Equip the HeroSword Animator controller, then configure its state or parameters with focused Animator actions.

Choose the target instance with the Action’s Applies To field.

Parameter	Type	Optional	Details
Animator	text	No	An Animator resource name. Blank returns to the model’s own Animator (or the automatic idle/walk).

Set Animator Layer

Changes one layer’s weight on the live instance’s Animator over the selected duration. Other layers continue playing.

Reference key: setAnimLayerWeight.

Editor category: 3D World > 3D Animation.

Availability: 3D Logic only.

Example: On Button Pressed [Attack]: Set Animator Layer [UpperBody] to [1] over [0.15] seconds.

Choose the target instance with the Action’s Applies To field.

Parameter	Type	Optional	Details
Layer	text	No	A layer name from the instance’s Animator (the Layers strip in the Animator Editor).
Weight	number	No	0 = the base machine alone, 1 = this layer fully owns its masked bones. Default: 1.
Seconds	number	Yes	0 applies instantly; otherwise the weight glides there. Default: 0.

Set Animator Parameter

Changes a value parameter on the live instance’s 3D Animator. The Animator’s transition conditions respond to that value. Use Fire Animator Trigger for a Trigger parameter.

Reference key: setAnimParam.

Editor category: 3D World > 3D Animation.

Availability: 3D Logic only.

Example: Set [aiming] to 1 while the bow is drawn; use Fire Animator Trigger for [attack].

Choose the target instance with the Action’s Applies To field.

Parameter	Type	Optional	Details
Parameter	text	No	A parameter declared on the instance’s Animator (speed, moving, grounded, vspeed, dirX and dirY are fed by the engine automatically when declared).
Value	number	No	Expression or literal value.

Set Animator Speed

Changes the playback rate of the live instance’s 3D Animator, including its layers, blends, and animation Events. A rate of 1 is normal speed, 0.5 is half speed, and 0 holds the current pose.

Reference key: setAnimatorSpeed.

Editor category: 3D World > 3D Animation.

Availability: 3D Logic only.

Example: On Custom Event [slowmo]: Set Animator Speed [0.25] on every enemy.

Choose the target instance with the Action’s Applies To field.

Parameter	Type	Optional	Details
Speed	number	No	1 = authored speed, 0.5 = half, 0 = frozen mid-pose. Default: 1.

Set Block

Places or replaces one block at a 3D Scene cell. Removing a block uses the separate Clear Block Atomic.

Reference key: setBlock.

Editor category: 3D World > 3D Blocks and Terrain.

Availability: 3D Logic only.

Example: A lever sets a stone step at one exact cell.

Parameter	Type	Optional	Details
Cell X	number	No	Block-grid column (one block per meter; Blender X).
Cell Y	number	No	Block-grid Y (north is +Y, as in Blender).
Cell Z (Level)	number	No	Block height level, Blender Z (the floor layer is 0).
Tileset	thing:tileset	No	The tileset whose Blocks (3D) palette names the block.
Block	text	No	A palette name from that tileset’s Blocks (3D) list.

Set Camera Control

Selects authored framing, player orbit controls, or first-person controls for the 3D Camera rig. Orbit uses the authored limits; first-person uses the follow Object and configured input.

Reference key: setCameraControl.

Editor category: 3D World > 3D Cameras.

Availability: 3D Logic only.

Example: A doorway trigger runs Set Camera Control [firstPerson]; the cutscene hands it back with [none].

Parameter	Type	Optional	Details
Mode	enum	No	Choose one of the listed options. Choices: orbit, firstPerson, none. Default: “orbit”.

Set IK Target

Selects the target for a named IK constraint on the live instance’s Model while animation continues. Look-at, two-bone, and chain constraints use this request. Ground Legs targets the surface automatically and ignores it.

Reference key: setIKTarget.

Editor category: 3D World > 3D Inverse Kinematics.

Availability: 3D Logic only.

Example: On Custom Event [grab]: Set IK Target [hand-r] mode [object], object [Lever] — the hand closes onto the lever mid-walk.

Choose the target instance with the Action’s Applies To field.

Parameter	Type	Optional	Details
IK Constraint	text	No	An IK constraint by name, authored in the 3D Model’s IK section.
Target	enum	No	point = the X/Y/Height below; object = follow an object; camera = the 3D camera; off = back to the animation. Choices: point, object, camera, off. Default: “point”.
Position Relative To	enum	Yes	World uses absolute scene coordinates. Object uses local offsets from the acting Object. Coordinate uses local offsets from a named Coordinate. Bounding Box uses local offsets from a selected Transform bounding-box anchor. Choices: world, object, coordinate, boundingBox. Default: “world”.
Coordinate	text	Yes	A named Coordinate on the acting Object. Used only when Position Relative To is Coordinate.
Bounding Box Anchor	enum	Yes	A point on the acting Object’s Transform bounding box. Used only when Position Relative To is Bounding Box. Choices: center, top, bottom, left, right, topLeft, topRight, bottomLeft, bottomRight. Default: “center”.
X	number	Yes	Target X in scene meters (point mode).
Y	number	Yes	Target Y in scene meters (point mode).
Z (Height)	number	Yes	Target height in meters (point mode), or a height offset in meters above the followed object (object mode).
Object	thing:object	Yes	The object to follow (object mode; the nearest live instance, re-resolved every frame).

Set Material

Assigns a 3D material to the live instance. Use Animate Material to change a property over time.

Reference key: setMaterial.

Editor category: 3D World > 3D Materials.

Availability: 3D Logic only.

Example: Skin the model with Stone, then use Animate Material for a changing emissive intensity.

Choose the target instance with the Action’s Applies To field.

Parameter	Type	Optional	Details
Material	thing:material	Yes	A Material resource name. Blank returns the model to its own materials.

Set Model Animation

Plays a named clip as an override on the live Model instance, blending over Blend Seconds. Its Animator continues underneath. A blank clip name or completion of a non-looping clip returns playback to the Animator or automatic animation.

Reference key: setModelAnimation.

Editor category: 3D World > 3D Animation.

Availability: 3D Logic only.

Example: On Custom Event [openChest]: Set Model Animation [Open], loop off.

Choose the target instance with the Action’s Applies To field.

Parameter	Type	Optional	Details
Animation	text	No	A glTF animation group name (blank fades back to the model’s Animator, or its automatic idle/walk).
Loop	boolean	Yes	On or off. Default: true.
Blend Seconds	number	Yes	Cross-fade time. 0 snaps. Default: 0.2.

Set Placed Effect

Turns a named Scene effect on or off. Off stops emission while existing particles finish. This state is included in saves; use a stable effect Name.

Reference key: setPlacedEffect.

Editor category: 3D World > 3D Effects.

Availability: 3D Logic only.

Example: On Custom Event [leverPulled]: Set Placed Effect [beacon] to [on] — the tower catches fire.

Parameter	Type	Optional	Details
Placed Effect	text	No	The stable Name of an effect placed in the 3D Scene (its name in the Scene Explorer).
Switch	enum	Yes	Choose one of the listed options. Choices: toggle, on, off. Default: “toggle”.

Set Sun Direction

Sets the 3D Scene’s sun direction. The sky follows the new direction, and the automatic day/night solar arc stops controlling the sun for the remainder of that Scene.

Reference key: setSunDirection.

Editor category: 3D World > 3D Lights and Shadows.

Availability: 3D Logic only.

Example: End Step: Set Sun Direction [-cos($sunAlt)*sin($sunAz), -sin($sunAlt), -cos($sunAlt)*cos($sunAz)] — an astronomical sun.

Parameter	Type	Optional	Details
Direction X	number	No	The direction sunlight travels, in the same convention as the Scene editor Sun. Only the direction matters, not the length. Default: -0.55.
Direction Y	number	No	Negative shines downward. A sun below the horizon shines upward. Default: -1.
Direction Z	number	No	Expression or literal value. Default: 0.35.
Intensity	number	Yes	Multiplies the authored sun strength: 1 is authored, 0 is dark. Blank keeps.

Spawn 3D Effect

Creates a transient 3D Effect at the acting Object, a selected position, or a position following the Object. The Effects (3D) quality tier limits live instances. Stop 3D Effects controls spawned effects; Set Placed Effect controls authored Scene effects.

Reference key: spawnEffect.

Editor category: 3D World > 3D Effects.

Availability: 3D Logic only.

Example: On Collision with [Barrel]: Spawn 3D Effect [Explosion] — then the barrel runs Destroy.

Choose the target instance with the Action’s Applies To field.

Parameter	Type	Optional	Details
3D Effect	thing:particle	No	The Particle resource (authored in the 3D space) to create.
Position Relative To	enum	Yes	World uses absolute scene coordinates. Object uses local offsets from the acting Object. Coordinate uses local offsets from a named Coordinate. Bounding Box uses local offsets from a selected Transform bounding-box anchor. Choices: world, object, coordinate, boundingBox. Default: “object”.
Coordinate	text	Yes	A named Coordinate on the acting Object. Used only when Position Relative To is Coordinate.
Bounding Box Anchor	enum	Yes	A point on the acting Object’s Transform bounding box. Used only when Position Relative To is Bounding Box. Choices: center, top, bottom, left, right, topLeft, topRight, bottomLeft, bottomRight. Default: “center”.
X (m)	number	Yes	World X in scene meters. Blank = at this object.
Y (m)	number	Yes	World Y in scene meters. Blank = at this object.
Z (Height)	number	Yes	Height in meters (Blender Z). Blank = this object’s height.
Follow me	boolean	Yes	The emitter rides this object as it moves (any X/Y/Height become offsets from it). Default: false.
Scale	number	Yes	Whole-effect size — 2 doubles the sizes, spread and speeds; 0.5 halves them. Default: 1.

Stop 3D Effects

Stops emission from matching spawned 3D Effects. Existing particles finish their lifetimes. Authored Scene effects are controlled separately with Set Placed Effect.

Reference key: stopEffects.

Editor category: 3D World > 3D Effects.

Availability: 3D Logic only.

Example: On Custom Event [rainStops]: Stop 3D Effects [Rainfall] everywhere — the last drops fall and the sky clears.

Choose the target instance with the Action’s Applies To field.

Parameter	Type	Optional	Details
3D Effect	thing:particle	Yes	Stop only this effect. Blank = every spawned effect in scope.
Which	enum	Yes	mine = effects this object spawned or that follow it; everywhere = every spawned effect in the scene. Choices: mine, everywhere. Default: “mine”.

Take Photo

Captures the current 3D view as a PNG, including its rendering effects. Camera zones with a Photo Quest name update the photo quest and count Globals. The named photoTaken3d Custom Event can respond to the capture.

Reference key: takePhoto3d.

Editor category: 3D World > 3D Cameras.

Availability: 3D Logic only.

Example: When [P] is pressed: Take Photo at width [1920], style [postcard].

Parameter	Type	Optional	Details
Width (px)	number	Yes	Capture width in pixels; height follows the screen aspect (64–4096). Postcard style captures at the classic 3:2 plate instead. Default: 1280.
File name	text	Yes	The saved PNG’s name (without extension). Default: “photo”.
Style	enum	Yes	Photo saves the raw capture; Postcard mounts a 3:2 shot on a bordered card whose caption strip reads the sealed plate (title · maker · date; an unsealed game signs with its project title). Choices: photo, postcard. Default: “photo”.